Energy Resources of Australia has extended the suspension of uranium processing operations at its Ranger mine from end-April through July.

The move, caused by heavy rainfall, is expected to cut 2011 uranium production from about 3,793 mt U3O8, similar to the 2010 level, to 2,400 mt U3O8, the company said Tuesday. In 2009, ERA produced 5,240 mt U3O8 at the Ranger mine.

The uranium processing suspension means ERA, a Rio Tinto-owned company, will have to buy uranium to meet its 2011 sales contracts totaling 4,500 mt, although the company said the majority of those purchases have already been made.

ERA said it now expects a first half 2011 loss of A$30 million-A$50 million ($31.64 million-$52.73 million), compared with a net profit of A$22.7 million in the first half of 2010. 

Mining operations have been severely hampered by above-average rainfall that limited access to higher-grade ore at the bottom of the mine.

ERA does not expect to obtain access to the high grade ore at the bottom of the mine until at least late 2011, the company said. The current Ranger open pit mine is scheduled to cease operations by the end of 2012, though the company is exploring new pits at the site.

On January 28, ERA announced a 12-week suspension of uranium processing operations to help ensure that levels in the Tailings Storage Facility remained below the authorized operating limit throughout the wet season, which typically runs through the end of April. 

Since that announcement, the Northern Territory has continued to receive significantly higher than average rainfall, the company said. While the water level in the TSF is below the authorized operating limit, the total process water inventory at Ranger has recently exceeded the level at which operations are able to re-commence, the company said. Therefore, it was forced to extend the suspension of uranium processing operations.

ERA said under the circumstances, it was conducting a comprehensive business review of ERA's current operations and future projects. The review will assess priorities, processes and future expenditure.